I'm a little fuzzy on your phrase "produce spiritual lives".
I seriously doubt that an entire one billion registered as such Catholics are entirely misguided, but we also need to remember that God once destroyed the entire world saving only 8 souls. It is possible that a great mass of folks in all stated churches(both Catholic and Protestant) are all following wrong paths. God seeks those who worship him in their hearts, who do so in spirit and in truth, he is not necessarily guided by the consensus of a billion Catholics.
He is certainly not guided by the concensus of a billion RCs.
I’m a little fuzzy on your phrase “produce spiritual lives”.
How about the term “spiritual fruits” then as in “by their fruits you will know them”.
The Holy Spirit works within a soul to produce a Christ like nature, there-fore any oral doctrines or traditions that may not be strictly found in scripture that never -theless assist that soul in its growth will have no opposition by the Holy Spirit. That soul will produce fruit
and a Godly character over time!
Other extra biblical doctrine, while being accepted/promoted by a given ecclesiastical authority, that works in opposition to the work of the Holy Spirit within a person will stunt the growth of that person producing little, or no, or even evil fruit.
That is why many believers look askance at oral traditions and teachings that may have no antecedents in scripture. Do such doctrines produce good spiritual fruit when adhered to? Are they true, good,beautiful and of “good report” as Paul stated? Then we may ‘dwell on those things’. Other wise we are to stick to the gospels!